Kilometre zero

In many countries, Kilometre Zero (also written km 0) is a particular location (often in the nation's capital city), from which distances are traditionally measured. A similar notion also exists for individual roads (that is, all locations on the road have a number, depending on their distance from that location).

For example, Spain has its Kilometre Zero in the center of the Plaza del Sol in Madrid; Chile's Autopista Central (the Chilean portion of the Panamerican Highway) has its Kilometre Zero at the intersection with the Alameda del Libertador Bernardo O'Higgins.